Raman O VI Profile Analysis of Accretion and Bipolar Outflow in Sanduleak's Star

Wednesday, 23 November 2016 8 a.m. — 9 a.m. MST

AURA Lecture Hall

NOIRLab South Colloquia
JEONG-EUN HEO (Dept. of Astronomy and Space Science, Sejong University, Korea, and Gemini-South Visiting Astronomer)

Raman-scattered O VI bands at 6825Å and 7082Å are unique spectroscopic features, which so far have been detected only in bona fide symbiotic stars. These bands are used as an useful diagnostic tool to investigate the mass transfer process of symbiotic stars. This talk will be focused on the profile analysis of two Raman O VI bands, which enable us to obtain quite detail information including the kinematics and the density distribution of O VI emission region.

Also we apply this approach to Sanduleak’s star, a suspected symbiotic binary in Large Magellanic Cloud. By performing careful profile analysis with the high-resolution MIKE spectrum, we suggest that the O VI emission region can be decomposed into: an accretion disk, a bipolar outflow and a compact, optically thick region around the white dwarf. Additionally our Monte Carlo result shows that the neutral region in Sanduleak’s star is characterized by the column density N_HI ~ 1 × 10^23 cm^-2.